Generally, an accelerometer is a device that may be configured to measure the acceleration of a given object. For example, typical accelerometers may be configured so as to measure the specific force, or g-force, experienced by such an object. A measurement of g-force provides an indication of the acceleration of the object relative to its inertial frame of reference.
As technologies involving guidance, navigation, control, and/or other motion-sensitive applications have become more pervasive, so too has the demand for accelerometers. Recently, accelerometers have been incorporated into many types of mass-produced commercial products, such as automobiles, pedometers, mobile phones, PDAs, and gaming consoles. As may be expected, as the degree of precision of a given accelerometer increases, typically so too does the design cost, manufacturing cost, and/or size of the accelerometer. On the other hand, if a high degree of precision is not required from a given accelerometer application, the size and cost of such an accelerometer may tend to be, respectively, relatively small and low. Many emerging technologies, including those involving the mass production of consumer products, place a relatively greater value on small size and low cost as compared to precision of accelerometers.
Accelerometers may generally take on many forms. In one common example, accelerometers may include an acceleration-detection component that measures some value indicative of a change in acceleration and then provides that measurement to a separate readout component for processing and/or analysis. Such an acceleration-detection component may include one or more of a variety of physical transduction mechanisms that convert physical motion of an object associated with acceleration into a processable signal potentially via microelectromechanical systems (MEMs) having one or more of capacitive, piezoelectric, optical and tunneling technologies.
While use of such MEMs technologies in accelerometers generally provides for stable and accurate acceleration detection, fabrication costs of such MEMs are typically relatively high due to their complicated structures and large size. Further, micromachining techniques used to integrate MEMs devices with integrated circuits (ICs) utilize nonstandard manufacturing technologies resulting in costs above and beyond those involved with manufacturing devices using standard IC processes.
The ability to integrate an accelerometer into an IC using standard techniques may provide many benefits, including accurate/reliable sensing of device orientation, shock detection/prediction, and motion detection at low cost.